Display panel, evaporation method of luminous material and equipment

ABSTRACT

A display panel, an evaporation method of a luminous material, and an equipment are provided. The method is performed by providing an electric field covering an array substrate, and generating luminous material charged particles. After the luminous material charged particles passing through the mask, they will change a direction of motion under an action of the electric field, and move perpendicularly to a pixel area of the array substrate along a direction of the electric field, and then uniformly deposit on the pixel area of the array substrate, which ensures that a uniformity of film formation of the luminous material.

RELATED APPLICATIONS

This application is a National Phase of PCT Patent Application No.PCT/CN2019/076912 having International filing date of Mar. 5, 2019,which claims the benefit of priority of Chinese Patent Application No.201811207832.5 filed on Oct. 17, 2018. The contents of the aboveapplications are all incorporated by reference as if fully set forthherein in their entirety.

FIELD AND BACKGROUND OF THE INVENTION

The present disclosure relates to the field of displays, and inparticular to a display panel, an evaporation method of a luminousmaterial, and an equipment.

In manufacture of OLED display panels, in general, an array substrate isfirstly fabricated, and then a luminous material is evaporated to apixel area of the array substrate by an evaporation process.

FIG. 1 shows an evaporation process in the prior art. A mask is alignedwith an array substrate, and then an evaporation source evaporates aluminous material. However, at a critical position of red (R), green(G), and blue (B) sub-pixels, the luminescent material will restrictedby a shadow of the mask. If a uniformity of film formation of theelectroluminescent (EL) material is poor, there is a color shift orcolor mixing problem at the critical position of the sub-pixels.

That is, an existing display panel has a technical problem that theuniformity of a film of the luminous material is poor at the criticalposition of the sub-pixels.

SUMMARY OF THE INVENTION

The present disclosure provides a display panel, an evaporation methodof a luminous material and an equipment, so as to solve the technicalproblem of a poor uniformity of film formation of the luminous materialat a critical position of sub-pixels in an existing display panel.

In order to solve the above problems, the technical solution provided bythe present disclosure is as follows.

The present disclosure provides an evaporation method for a luminousmaterial, including:

aligning a mask with an array substrate;

generating an electric field covering the array substrate; and

processing the luminous material to generate luminous material chargedparticles, where after the luminous material charged particles passthrough the mask, they are deposited on a pixel area of the arraysubstrate under the electric field.

In the evaporation method for the luminous material of the presentdisclosure, in the step of generating the electric field covering thearray substrate, the method includes:

grounding the mask; and

supplying power to an electric-field electrode, where the electric-fieldelectrode is parallel to the mask, and the array substrate is locatedbetween the electric-field electrode and the mask.

In the evaporation method for the luminous material of the presentdisclosure, in the step of generating the luminous material chargedparticles, the method includes:

outputting luminous material particles by a luminous materialevaporation source; and

controlling electric charges of the luminous material particles having aspecific polarity.

In the evaporation method for the luminous material of the presentdisclosure, the method further includes: supplying power to a circuit ofthe array substrate.

In the evaporation method for the luminous material of the presentdisclosure, in the step of supplying power to the circuit of the arraysubstrate, the method includes: supplying power to the circuit of thearray substrate by a thin film transistor circuit of the arraysubstrate.

In the evaporation method for the luminous material of the presentdisclosure, the method further includes: disposing a conducting post ona surface of a pixel definition layer of the array substrate.

In the evaporation method for the luminous material of the presentdisclosure, the method further includes: supplying power to theconducting post disposed on the surface of the pixel definition layer ofthe array substrate.

In the evaporation method for the luminous material of the presentdisclosure, in the step of supplying power to the conducting postdisposed on the surface of the pixel definition layer of the arraysubstrate, the method includes: electrically connecting the conductingpost to a conductive terminal of an evaporation equipment, and supplyingpower to the conducting post by the conductive terminal of theevaporation equipment.

The present disclosure provides a display panel, including: an arraysubstrate, a pixel definition layer disposed on the array substrate, anda luminous material layer in a pixel area defined by the pixeldefinition layer, where the luminous material layer is formed by theevaporation method of the luminous material provided by the presentdisclosure.

In the display panel of the present disclosure, the display panelfurther includes a plurality of conducting posts disposed on a surfaceof the pixel definition layer of the array substrate.

In the display panel of the present disclosure, the plurality ofconducting posts are continuously arranged to form a supporting wall.

In the display panel of the present disclosure, the display panelfurther includes an encapsulation layer disposed on the pixel definitionlayer and the luminous material layer.

In the display panel of the present disclosure, the encapsulation layerincludes a first inorganic layer, a second inorganic layer, and anorganic layer disposed between the first inorganic layer and the secondinorganic layer.

The present disclosure also provides an evaporation equipment for aluminous material, including:

an alignment module configured to align a mask with an array substrate;

an electric field module configured to generate an electric fieldcovering the array substrate; and

a charged ion module configured to process the luminous material togenerate luminous material charged particles, where after the luminousmaterial charged particles pass through the mask, they are deposited ona pixel area of the array substrate under the electric field.

In the evaporation equipment for the luminous material of the presentdisclosure, the evaporation equipment further includes an electric-fieldelectrode, where the electric-field electrode is parallel to the mask.

In the evaporation equipment for the luminous material of the presentdisclosure, the evaporation equipment further includes a first powersupply module configured to supply power to a circuit of the arraysubstrate.

In the evaporation equipment for the luminous material of the presentdisclosure, the evaporation equipment further includes a second powersupply module configured to supply power to a conducting post disposedon a surface of a pixel definition layer of the array substrate.

In the evaporation equipment for the luminous material of the presentdisclosure, the charged ion module includes an evaporation source and acharge source, and the evaporation source is configured to control aluminous material evaporation source to output luminous materialparticles, and the charge source is configured to control electriccharges of the luminous material particles having a specific polarity.

In the evaporation equipment for the luminous material of the presentdisclosure, the charge source includes a mesh charging structure.

In the evaporation equipment for the luminous material of the presentdisclosure, the electric field module includes a ground terminal and anelectric field power terminal, and the electric field power terminal isconfigured to output an electric field voltage, and in operation, themask is grounded through the ground terminal, and the electric-fieldelectrode obtains an electric field voltage through the electric fieldpower terminal to form the electric field.

Advantages of the present disclosure are as follows. The presentdisclosure provides a new evaporation technique for a luminous material,including aligning a mask with an array substrate; generating anelectric field covering the array substrate; and processing the luminousmaterial to generate luminous material charged particles, where afterthe luminous material charged particles pass through the mask, they aredeposited on a pixel area of the array substrate under the electricfield. By providing the electric field covering the array substrate andgenerating the luminous material charged particles, these luminousmaterial charged particles will change a direction of motion under anaction of the electric field after passing through the mask. Theluminous material charged particles are vertically moved toward a pixelarea of the array substrate along a direction of the electric field, andthen uniformly deposited on the pixel area of the array substrate, andare not deposited in a pixel critical position along an original movingdirection, nor deposited in other positions. A The uniformity of filmformation of the luminous material is ensured, and the technical problemof a poor uniformity of film formation of the luminous material at thecritical position of sub-pixels existing in the existing display panelis solved, and a color shift or color mixing problem at the criticalposition of the sub-pixels is also solved.

BRIEF DESCRIPTION OF THE SEVERAL VIEW OF THE DRAWINGS

In order to illustrate the technical proposal of implementations of theembodiments of the present disclosure or existing technology clearly,With reference to the accompanying drawings, the description of theimplementations of the present disclosure or existing technology aregiven as following briefly. Obviously, the given accompanying drawingsare only implementations of the present disclosure, so that, those ofordinary skill in the art could get other accompanying drawings inaccordance with the accompanying drawings without devoting a creativeeffort.

FIG. 1 is a schematic diagram of an evaporation process in the priorart.

FIG. 2 is a first flowchart of an evaporation method according to anembodiment of present disclosure.

FIG. 3 is a schematic diagram of an evaporation equipment according toan embodiment of present disclosure.

FIG. 4 is a second flowchart of an evaporation method according to anembodiment of present disclosure.

FIG. 5 is a first schematic diagram of a display panel according to anembodiment of present disclosure.

FIG. 6 is a second schematic diagram of a display panel according to anembodiment of present disclosure.

FIG. 7 is a third schematic diagram of a display panel according to anembodiment of present disclosure.

FIG. 8 is a fourth schematic diagram of a display panel according to anembodiment of present disclosure.

DESCRIPTION OF SPECIFIC EMBODIMENTS OF THE INVENTION

The foregoing objects, features and advantages adopted by the presentdisclosure can be best understood by referring to the following detaileddescription of the preferred embodiments and the accompanying drawings.Furthermore, directional terms described in the present disclosure, suchas upper, lower, front, rear, left, right, inner, outer, side and etc.,are only directions referring to the accompanying drawings, so that theused directional terms are used to describe and understand the presentdisclosure, but the present disclosure is not limited thereto. In thedrawings, similar structural units are designated by the same referencenumerals.

The present disclosure can solve shortcomings of the technical problemof a poor uniformity of film formation of the luminous material at acritical position of sub-pixels in an existing display panel.

In one embodiment, as shown in FIG. 2, an evaporation method of aluminous material provided by the embodiment of the present disclosureincludes the following steps.

In a step S201, a mask is aligned with an array substrate.

In a step S202, an electric field covering the array substrate isgenerated.

In a step S203, the luminous material is processed to generate luminousmaterial charged particles. After the luminous material chargedparticles pass through the mask, they are deposited on a pixel area ofthe array substrate under the electric field.

In an embodiment, the step S202 includes: grounding the mask andsupplying power to the electric-field electrode. The electric-fieldelectrode is parallel to the mask, and the array substrate is locatedbetween the electric-field electrode and the mask. For example, the maskis grounded and serves as another electrode for the electric field. Theelectric-field electrode is disposed under a thin film transistor (TFT)substrate. A vertical electric field is formed between the mask and theTFT substrate, so that charged particles of an electroluminescent (EL)material are evaporated to a surface of the TFT substrate in a verticaldirection.

In an embodiment, the step S203 includes: outputting luminous materialparticles by a luminous material evaporation source, and controllingelectric charges of the luminous material particles having a specificpolarity. For example, when the EL material is heated in the evaporationequipment, the evaporation source takes place in a form of electronflux.

Since a large number of charged particles accumulate on the surface ofthe substrate, particles of the same polarity tend to repel each other.When accumulating excessive electric charges, it is easy to causeelectrostatic damage. Therefore, current is fed to a TFT circuit duringthe evaporation process, and the charged particles reach the surface ofthe substrate and are electrically neutral. In one embodiment, beforethe step S203 of the method shown in FIG. 2, the method furtherincludes: supplying power to a circuit of the array substrate toneutralize the electric charges of the luminous material chargedparticles deposited at the position of the pixels.

In an embodiment, the step of supplying power to the circuit of thearray substrate includes: supplying power to a circuit of the arraysubstrate by a thin film transistor (TFT) circuit of an array substrate.

In an embodiment, in order to better enhance an anti-interferenceperformance between sub-pixel areas, the present disclosure furtherincludes a step of disposing a conducting post on a surface of a pixeldefinition layer of the array substrate. Before the evaporation of thepresent disclosure, a cylindrical structure is formed on the surface ofthe substrate to resist and support. In a structure of a phosphorescentmaterial (a kind of luminous material) for evaporation, since a tripletexcited state has a long life cycle, it is easy to diffuse a longdistance in elements to make color impure, and the luminous efficiencyis low, thereby affecting a lifetime. Adding this cylindrical structureensures high light transmittance and does not affect display. In theevaporation process, an evaporation color mixing can be blocked. Afterassembly, it can block an excitatory diffusion and avoid affecting thelifetime.

In one embodiment, before the step S203 of the method shown in FIG. 2,the method further includes: supplying power to the conducting postdisposed on the surface of the pixel definition layer of the arraysubstrate to prevent deposition of the luminous material chargedparticles on the conducting post.

In one embodiment, the step of supplying power to the conducting postdisposed on the surface of the pixel definition layer of the arraysubstrate includes: electrically connecting the conducting post to aconductive terminal of the evaporation equipment, and supplying power tothe conducting post by the conductive terminal of the evaporationequipment.

In one embodiment, as shown in FIG. 3, an evaporation equipment for aluminous material provided by an embodiment of the present disclosureincludes:

An alignment module (not shown in FIG. 3) is configured to align a mask4 with an array substrate 5 in precise alignment, where the alignmentmodule is generally a robot or the like.

An electric field module 31 is configured to generate an electric fieldcovering the array substrate.

A charged ion module 32 is configured to process the luminous materialto generate luminous material charged particles, where after theluminous material charged particles pass through the mask, they aredeposited on a pixel area of the array substrate under the electricfield.

In one embodiment, as shown in FIG. 3, the charged ion module 32includes an evaporation source 321 and a charge source 322. Theevaporation source 321 is used to control the luminous materialevaporation source outputting luminous material particles, and thecharge source 322 is used to control electric charges of the luminousmaterial particles having a specific polarity.

In one embodiment, the charge source 322 includes a mesh chargingstructure. The luminous material particles will be charged after passingthrough the structure, to form the luminous material charged particles.

In one embodiment, the evaporation equipment for the luminous materialfurther includes an electric-field electrode 6. The electric-fieldelectrode 6 is parallel to the mask 4.

In one embodiment, as shown in FIG. 3, the electric field module 31includes a ground terminal 311 and an electric field power terminal 312.The electric field power terminal 312 is used to output an electricfield voltage. In operation, the mask 4 is grounded through the groundterminal 311, and the field electrode 6 acquires the electric fieldvoltage through electric field power terminal 312. On this basis, theelectric field is formed.

In one embodiment, the evaporation equipment further includes a firstpower supply module for supplying power to the circuit of the arraysubstrate.

In one embodiment, the evaporation equipment further includes a secondpower supply module for supplying power to conducting posts disposed onthe surface of the pixel definition layer of the array substrate.

In one embodiment, as shown in FIG. 4, an evaporation method of aluminous material provided by an embodiment of the present disclosureincludes the following steps.

In a step S401, an array substrate with a pixel definition layer isprovided.

The array substrate is provided as shown in FIG. 5, and an area formedby the pixel definition layer is a pixel area.

In a step S402, as shown in FIG. 6, conducting posts 8 are disposed onthe pixel definition layer.

In one embodiment, the conducting posts may be continuously arranged toform a supporting wall.

In a step S403, an anode layer is formed on the pixel area.

In the step S403, a mask is aligned with the array substrate.

In a step S404, an electric field covering the array substrate isgenerated. Power is supplied to a circuit of the array substrate and theconducting posts.

The mask 4 is grounded through the ground terminal 321, and theelectric-field electrode 6 acquires the electric field voltage throughthe electric field power terminal 322 to form the electric field.

In a step S405, the luminous material is processed to generate luminousmaterial charged particles. After the luminous material chargedparticles pass through the mask, they are deposited on the pixel area ofthe array substrate under the electric field.

In a step S406, a cathode layer is formed on the pixel area, and it isencapsulated to obtain a display panel as shown in FIG. 7.

In an embodiment, as shown in FIG. 7, the display panel provided by anembodiment of the present disclosure includes an array substrate 71, aplanarization layer 72 disposed on the array substrate 71, a pixeldefinition layer 73 disposed on the planarization layer 72, an OLEDdevice 74 disposed in a defined area of the pixel definition layer 73and in contact with the array substrate 71 through the planarizationlayer 72, and an encapsulation layer 75 covering the OLED device 74, thepixel definition layer 73, and the array substrate 71.

In one embodiment, the array substrate includes a substrate and a thinfilm transistor array disposed on the substrate, metal traces, and thelike.

Generally, the planarization layer 72 is an organic layer and configuredto planarize the array substrate 71.

Similarly, the pixel definition layer 73 is also made by using anorganic material. It can be understood that the planarization layer 72and the pixel definition layer 73 can be patterned in one mask process.

The defined area refers to an area vacated by the pixel definition layer73 when the pixel definition layer 73 is formed, for forming an organicluminous material (a luminous layer) in the defined area in a subsequentprocess. The OLED device 74 is composed of an anode 741, an organiclayer 742, and a cathode 743. As shown in FIG. 8, the organic layer 742includes a hole injection layer 7421, a hole transport layer 7422, aluminous layer 7423, an electron transport layer 7424, and an electroninjection layer. 7425. The luminous layer 7423 is formed by anevaporation method provided by the present disclosure.

In one embodiment, as shown in FIG. 7, the encapsulation layer 75includes a first inorganic layer 751, a second inorganic layer 752, andan organic layer 753 disposed between the first inorganic layer 751 andthe second inorganic layer 752.

In an embodiment, as shown in FIG. 7, the display panel further includesconducting posts 8 disposed on a surface of the pixel definition layer73 of the array substrate.

In one embodiment, the conducting posts are continuously arranged toform a supporting wall.

According to the above embodiments, it can be known that:

The present disclosure provides a new evaporation technique for aluminous material, including aligning a mask with an array substrate;generating an electric field covering the array substrate; andprocessing the luminous material to generate luminous material chargedparticles, where after the luminous material charged particles passthrough the mask, they are deposited on a pixel area of the arraysubstrate under the electric field. By providing the electric fieldcovering the array substrate and generating the luminous materialcharged particles, these luminous material charged particles will changea direction of motion under an action of the electric field afterpassing through the mask. The luminous material charged particles arevertically moved toward a pixel area of the array substrate along adirection of the electric field, and then uniformly deposited on thepixel area of the array substrate, and are not deposited in a pixelcritical position along an original moving direction, nor deposited inother positions. A The uniformity of film formation of the luminousmaterial is ensured, and the technical problem of a poor uniformity offilm formation of the luminous material at the critical position ofsub-pixels existing in the existing display panel is solved, and a colorshift or color mixing problem at the critical position of the sub-pixelsis also solved.

In conclusion, although the present disclosure has been described withreference to the preferred embodiments thereof, it is apparent to thoseskilled in the art that a variety of modifications and changes may bemade without departing from the scope of the present disclosure which isintended to be defined by the appended claims.

What is claimed is:
 1. An evaporation method for a luminous material,comprising: aligning a mask with an array substrate; disposing aconducting post on a surface of a pixel definition layer of the arraysubstrate; supplying power to the conducting post disposed on thesurface of the pixel definition layer of the array substrate; generatingan electric field covering the array substrate; and processing theluminous material to generate luminous material charged particles,wherein after the luminous material charged particles pass through themask, they are deposited on a pixel area of the array substrate underthe electric field, wherein in the step of supplying power to theconducting post disposed on the surface of the pixel definition layer ofthe array substrate, the method comprises: electrically connecting theconducting post to a conductive terminal of an evaporation equipment,and supplying power to the conducting post by the conductive terminal ofthe evaporation equipment.
 2. The evaporation method for the luminousmaterial as claimed in claim 1, wherein in the step of generating theelectric field covering the array substrate, the method comprises:grounding the mask; and supplying power to an electric-field electrode,wherein the electric-field electrode is parallel to the mask, and thearray substrate is located between the electric-field electrode and themask.
 3. The evaporation method for the luminous material as claimed inclaim 1, wherein in the step of generating the luminous material chargedparticles, the method comprises: outputting luminous material particlesby a luminous material evaporation source; and controlling electriccharges of the luminous material particles having a specific polarity.4. The evaporation method for the luminous material as claimed in claim1, further comprising: supplying power to a circuit of the arraysubstrate.
 5. The evaporation method for the luminous material asclaimed in claim 4, wherein in the step of supplying power to thecircuit of the array substrate, the method comprises: supplying power tothe circuit of the array substrate by a thin film transistor circuit ofthe array substrate.
 6. A display panel, comprising: an array substrate,a pixel definition layer disposed on the array substrate, and a luminousmaterial layer in a pixel area defined by the pixel definition layer,wherein the luminous material layer is formed by the evaporation methodof the luminous material according to claim
 1. 7. The display panel asclaimed in claim 6, further comprising a plurality of conducting postsdisposed on a surface of the pixel definition layer of the arraysubstrate.
 8. The display panel as claimed in claim 7, wherein theplurality of conducting posts are continuously arranged to form asupporting wall.
 9. The display panel as claimed in claim 6, furthercomprising an encapsulation layer disposed on the pixel definition layerand the luminous material layer.
 10. The display panel as claimed inclaim 9, wherein the encapsulation layer comprises a first inorganiclayer, a second inorganic layer, and an organic layer disposed betweenthe first inorganic layer and the second inorganic layer.
 11. Anevaporation equipment for a luminous material, comprising: an alignmentmodule configured to align a mask with an array substrate; an electricfield module configured to generate an electric field covering the arraysubstrate; a charged ion module configured to process the luminousmaterial to generate luminous material charged particles, wherein afterthe luminous material charged particles pass through the mask, they aredeposited on a pixel area of the array substrate under the electricfield; and a second power supply module configured to supply power to aconducting post disposed on a surface of a pixel definition layer of thearray substrate, wherein the conducting post is electrically connectedto a conductive terminal of the evaporation equipment, and power issupplied to the conducting post by the conductive terminal of theevaporation equipment.
 12. The evaporation equipment for the luminousmaterial as claimed in claim 11, further comprising an electric-fieldelectrode, wherein the electric-field electrode is parallel to the mask.13. The evaporation equipment for the luminous material as claimed inclaim 11, further comprising a first power supply module configured tosupply power to a circuit of the array substrate.
 14. The evaporationequipment for the luminous material as claimed in claim 11, wherein thecharged ion module comprises an evaporation source and a charge source,and the evaporation source is configured to control a luminous materialevaporation source to output luminous material particles, and the chargesource is configured to control electric charges of the luminousmaterial particles having a specific polarity.
 15. The evaporationequipment for the luminous material as claimed in claim 14, wherein thecharge source comprises a mesh charging structure.
 16. The evaporationequipment for the luminous material as claimed in claim 11, wherein theelectric field module comprises a ground terminal and an electric fieldpower terminal, and the electric field power terminal is configured tooutput an electric field voltage, and in operation, the mask is groundedthrough the ground terminal, and the electric-field electrode obtains anelectric field voltage through the electric field power terminal to formthe electric field.